Influence of life in high-risk population. People who are genetically predisposed to obesity and related diseases are at greater risk if you stick to the modern lifestyle. Well studied, many amazing examples of the influence of lifestyle on change of body weight.
Due to significant changes in their traditional way of life for the past 50 years among the Indians of the tribe of Pima, Arizona, was living in the widespread obesity and diabetes. Today, Indians eat foods high in fat (50% of energy intake), which the market a large amount, while their traditional diet is low in fat (only 15% of energy intake). In addition, modern Indians lead a sedentary life, unlike their ancestors, farmers. In contrast, Indians Pima, who live in the mountains of the Sierra Madre in northern Mexico and are not influenced by the West, use traditional food and physical activity, as work on farms and logging operations. At the same time the incidence of obesity and diabetes among them is much lower than that of genetically related Indians in Arizona.
Another example is the Aboriginal population of northern Australia. Those of them who live in cities, more often develop type 2 diabetes and hypertriglyceridemia, in addition they have a greater weight than is usually pretty thin (BMI <20 kg/m2), Aborigines, who lead a traditional life of hunters and gatherer. Return of urban Aboriginal with type 2 diabetes and hypertriglyceridemia, 7 weeks in traditional terms: a way of life of hunters and gatherers, to a low-fat and low calorie diet, consisting of game, fish and plants to high physical activity, led to reduce their weight, a significant improvement or even normalization of blood glucose, insulin and triglyceride levels and glucose tolerance. In Papua New Guinea, the prevalence of obesity in the rural Highlands is about 3%, while in urban areas are obese 38% of the population.
The influence of lifestyles at an early age. Even in the early life conditions may affect the change in body weight or metabolic abnormalities develop in the future. The study found that boys and girls who were born prematurely and had low weight at birth, later had a higher BMI, a ratio of greater circumference of chest to thigh circumference, as well as more developed metabolic syndrome than in those born with normal weight and in time. The essence of this phenomenon is not completely clear, but there is a hypothesis that fetal malnutrition and intrauterine growth retardation have a prolonged effect on the function of internal organs.
The nature of food in childhood can also affect the change in body weight in the future. Crossover study of 13 345 children in Bavaria, Germany, showed that breastfeeding for the first year of life reduces the risk of overweight or obese at the age of 5-6 years. Moreover, the protective effect of breastfeeding is manifested regardless of social status or lifestyle.
The influence of childhood obesity and the presence of his parents. Obesity in childhood and the presence of his parents increases the risk of obesity in adulthood. The data of a randomized trial showed that among young adults (21-29 years) the risk of obesity ranged from 8% in those who were obese at the age of 1 to 2 years of age and parents are not obese, and 79% in those who developed obesity at the age of 10-14 years and at least one parent was obese.
That is, the likelihood of developing obesity in adulthood increases depending on the age of occurrence and severity of childhood obesity. Children 1 to 2 years old, obese but whose parents were lean, had practically no risk of obesity in adulthood, while those who developed obesity after 6 years of age, the risk of developing it at maturity was already 50%. In addition, the presence of obesity in one or both parents also increased the risk. Skinny kids with at least one parent is obese, had higher (three times) the risk of obesity in adulthood.